In a printing system, such as an offset printer, digital printing press, copier, and so forth, it is often desirable to evaluate the quality of the printed product while the system is in the process of executing the print job. The need to evaluate the printed product is especially apparent when the printing system is producing high-quality documents that are subject to approval by a customer. In order to evaluate samples of the printed product, the printing system operator is often required to periodically remove one or more of the printed documents from the printing system""s output tray. If the printing system operator determines that the print quality has noticeably degraded, the operator can stop the print job and make adjustments to improve the quality of the documents printed by the printing system.
However, when the printing system is printing a publication such as a book or pamphlet, in which multiple single-page documents are included in the book or pamphlet, the removal of a single document from the printing system""s page stream can adversely affect the page order. Thus, when a sample page is removed, the page must be reinserted into the printed output stack so that each copy of the completed publication includes the correct number of documents. However, in a high speed printing environment, the reinsertion of a previously removed page can be problematic.
Further, in the event that the printing system is printing a variable data document as part of a variable document print campaign, in which text and/or images are placed within copy holes according one or more rules that control the print campaign, the printing system operator may not have knowledge of when a particular variable data document is to be output from the printing system. This can be especially true when the printing system is a digital printing press in which a system controller determines which variable text and images are to be placed within a particular variable data document""s copy holes only moments before the finished document is printed and routed to an output tray.